1. Field of the Invention
In one embodiment, the present invention relates to nucleic acid constructs and methods of using these constructs to rapidly screen for target molecule interactions. More particularly, an RNA/DNA chimera comprising a fluorophore-quencher pair and a nucleic acid construct is disclosed for the rapid screening of interactions between the HIV-1 nucleocapsid protein, NCp7, and a stem-loop region, SL3, of the HIV-1 RNA, or antagonists thereof; this interaction is primarily responsible for packaging specificity in HIV-1. The compositions and methods disclosed herein can be used in preferred aspects of the present invention for diagnosing disease states, distinguishing the presence of infectious or toxic agents, drug discovery and design, and molecular electronic applications.
2. Description of the Related Art
HIV-disease causes great suffering and death in the U.S., and millions are dying worldwide. Even though the number of deaths in the United States from HIV-disease has declined in recent years, the worldwide epidemic is out of control. This ever-larger number of infected people is a direct threat to everyone because HIV-1 mutates so rapidly. The larger the pool of infected individuals, the more rapidly drug-resistant strains will emerge. The reverse transcriptase makes so many errors that every single point mutation occurs daily in newly infected cells (Coffin, J. M. (1995) Science 267:483-9), and nearly 1% of all possible double mutations occur (Perelson, A. S. et al. (1997) AIDS 11 (suppl. A) S17-34). Combinations of drugs used in “Highly Active AntiRetroviral Therapy” (HAART) treatment regimes target different parts of the viral life cycle. In the face of such a high mutation rate, it is clear that failures in the HAART approach must occur with increasing frequency using existing drugs. Resistant strains already exist for all currently used protease and reverse transcriptase inhibitors (Pillay, D. et al. (2000) Rev. Med. Virol. 10:231-53), the most potent weapons in the battle against AIDS.
Even if an effective vaccine is developed to prevent new HIV-1 infections, there will still remain a need to treat millions of AIDS victims. Their long-term treatment will require new generations of drugs. Anti-nucleocapsid protein drugs, as well as agents directed at other potential HIV targets, such as anti-rev and anti-tat, could be combined with current and next generation drugs for a multi-pronged attack that would be difficult for the virus to evade. Adding these drugs to present HAART treatments may provide highly specific and potent antiretroviral treatments. Such drugs may greatly diminish the devastating effects of HIV-related disease around the world.